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Question 56 in our cryptic quiz: “Three is the magic number”

Half way there today – and the story is starting to come to an end. Keep focused though, as there are lots of great prizes up for grabs. Good luck…

Domicile03, Baby Bear’s Task

I like children, really I do. Even precocious children like Baby bear. But after the nth question of, “Whatchya doin’, Aunt Erin?” I’d had quite enough, thank you.

“Baby bear,” I said, “I need you to do me a favor. I’ve got three switches on the first floor of my house that turn on three light in three different rooms upstairs. I’ve never managed to figure out which switch turns on which bulb, so I need you to figure it out for me. You can flip the switches as many times as you want and leave them in any position that you want, but because my house wasn’t built for bears, you can only safely take one trip upstairs to check the bulbs themselves.”
“Oh sure, Aunt Guin,” he said, “I can do that easily!”

Well drat. I had hoped it would keep him occupied for a while. I mean, of course I knew which switch went to which bulb. I’m not an idiot.

QUESTION: What did baby do to determine which switch belonged to which bulb?

Post your answers below, and come back in a few hours for Friday’s final installment.

Turn two switches on for a minute or two. Then switch one of them off. Now there should be two switches off and one on. Go upstairs. The bulb that is on obviously corresponds to the switch that is on. Touch the other two bulbs. The one that is cold is the one that was never switched on, while the one that is warm to the touch is the one that was switched on and then off.

Turn two switches on. Wait a bit, then turn one off. Go upstairs. One light will be on, one off, the other still warm. Warm one is the one you switched off just before going upstairs, switch that you turned on will be on, and one you left off will be off.

Baby turned one switch on for a few minutes to allow the lightbulb to heat up. He then switch that switch off and turned on another one and went upstairs. He quickly checked the two that were off to see which was still warm, therefore matching all three switches with bulbs.

Baby bear leaves one switch off. He turns a second switch on, and then waits 5 or 10 minutes before turning the third switch on. He immediately makes his one permitted trip upstairs. The off-switch/off-light combo is obvious, and Baby then feels the two lightbulbs that were turned on. The hotter lightbulb belongs to the switch he turned on first, while the cooler lightbulb belongs to the switch that he only just flipped on.

Baby flipped two of the switches to the ON position and waited for a time. He then flipped one of those two ON switches to OFF and went upstairs.

The lit bulb corresponds to the switch that is ON. Of the two remaining unlit bulbs, the cold one was the switch that stayed in the OFF position, while the unlit bulb that was still warm to the touch had its switch turned ON and OFF.

Ok…here’s my attempt:
1) He turned all switches off until the bulbs cooled down
2) Turned on 1st switch for a few minutes
3) Turned off the 1st switch then turned the 2nd switch on
4) Went upstairs
5) Whichever light was on was the 2nd switch
6) Whichever light was off but warm was the 1st switch
7) The light that was off but COLD was the 3rd switch

Turn one switch on and wait a few minutes. Turn it off and flip another switch on. Go upstairs. The switch that was just flipped is the light that’s on. Feel the two bulbs that are off. The switch that was flipped first will have a hot bulb. The switch that was never touched is the normal temp bulb.

Turn on the first light switch and wait five minutes. Then turn it off and turn on the second light switch. Go upstairs; the light that’s on is the second switch, and if you touch the other two bulbs the hot one is the first switch and the cold one is the third switch.

Flip on switch A for a few minutes, then switch it off and flip on switch B. Now baby can go upstairs and see: the bulb which is on is obviously connected to switch B; the warm bulb is connected to switch A; and the cold one is connected to switch C.

Turn on two switches, wait several minutes and then turn one of them off. Go upstairs to check the bulbs. One bulb should be off, but warm. That one is controlled by the switch that was turn on and then off. The bulb that is still on goes to the switch that was left on, and the bulb that’s off goes to the remaining switch that was never used.

Baby should start by switching the switches thus:
Switch the first switch on, and leave it on.
Leave the second switch in the off position.
Switch the third switch on, but turn it off after about half an hour.

After he’s waited the half hour and turned off the third lightbulb, he should go upstairs to check on the lights:
The lightbulb still lit will be the first switch.
The lightbulb that is off, and cold, will be the second switch.
The lightbulb that is off, but still warm from being left on for the last half hour, is the third switch.

This is assuming that the bulbs aren’t the energy efficient sort that don’t really warm up!

Baby Bear flipped the switches and left them on for different lengths of time. Then made the trip upstairs to test the temperatures of the light bulbs to coincide with the length of time each switch was flipped “on”.

Presuming it’s a two-storey house in the UK, the first floor (where the switches are) *is* upstairs, so baby bear should just be able to leave the doors to the rooms open and see the lights going on and off as he flicks the switches.

He flicked on the first switch, let it open for a while, then flicked it off.
He flicked on the second switch and left it on.
Then he sauntered up the stairs.
The lightbulb that was lit, went with the second switch.
The lightbulb that was still hot went with the first one and the one that remained with the third one.

Turned on two light switches, left them on for five minutes and turned one off. Ran upstairs: The one that was still on was the one baby left on; the one that was still warm and off was the one baby just shut off, and the cold one left was the one never turned on.

He has to turn the first switch on and wait for a while to heat up the bulb. Then he has to turn the first switch off and the second switch on. Than he has to go upstairs and try which of the bulbs is hot but no light on – this will be the first switch. The bulb where the light is on will be the second switch and the bulb which is cold and no light on belongs to the last switch.

Turn on first switch and wait half an hour. Then turn it off and turn on second switch. Go upstairs. The lit bulb is connected to the second switch and the warm bulb is connected to first switch. The bulb that is not lit and still cold is the third switch.

Turn one light on for a few minutes then turn it off and another switch on, and go upstairs. The light that is on is linked to the second switch, and the bulb that is hot but off is linked to the first switch. The cold and off bulb is linked to the last switch.

He turned Light #1 on for a few minutes (to heat up the bulb) and turned it off.
He left Light #2 on.
He left Light #3 off.
When he goes upstairs, Light #1 will be warm but off. Light #2 will be on and Light #3 will be off and cold.

Baby bear should flip one switch and wait about five minutes. He should turn that switch off and turn another one on. Then, he should run upstairs and touch the two bulbs that are not lit.

The hot/warm one will be the first switch he turned on. The bulb that is lit will be the switch currently in the ‘On’ position and the bulb that is not lit will be the one that is in the ‘off’ position.

Switch on the first switch. Leave it on for some time (15 minutes or so). Turn it off again.
Turn on the second switch.
Leave the 3rd switch off.

Go upstairs. The room with no light on but with a WARM bulb, connects to switch one.
The room with the light on connects to switch 2.
the room with the cold bulb and no light on connects to bulb 3.
et voila!

Turn one switch on and wait for a little while. Then turn it off and turn on a second switch. Once you get upstairs, the light that’s on is the second switch. Touch the remaining two light bulbs. The light that is off but warm is the first switch. The light that is off and cool is the third switch.

The first switch has to be put on, the second has to be put on for some minutes and then put off again, and the third switch has to stay in off-position. Upstairs the lit lightbulb will belong to the first switch, the hot one will belong to the second switch and the cold one belongs to the third switch.

He turned two switches on. Left them like that for a few minutes. Then turned one off. Went upstairs. The room with no light and a cool bulb was the untouched switched. The room with no light and a hot bulb was the switched turned on for a few minutes and then off. The room with the light on is the switch left on!

I always hated these logic puzzles! So turn on switches 1 and 2. Wait a few minutes and turn the first one off. Go upstairs to check them. The one that’s on is #2. The one that is off but warm is #1. The one that is off but cold is #3.

He makes sure all the light switches are off. Then turns on switch 1 and leaves on for several minutes. He turns on switch 2 and heads upstairs. If the bulb is on, then he knows it is switch 2. If it’s off and he touches the bulb but it is hot, then he knows it is switch 1. If it’s off nad cold, then it is switch 3.

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